I run TS2009 in both SLI and non-SLI.
I have 2 x6800GT nvidia graphics cards. The latest nvidia drivers. You go into nvidia control panel making sure you are in single monitor situation and select SLI.
I have found it a little finicky to get into SLI. You may have to experiment with resolution and refresh rate. And you may have to restart computer.
Once in SLI mode there is nothing special you have to do. Just start TS2009. Benefit is much higher FPS and faster graphics where you are graphics performance limited, but it won't do much for any situation where you are CPU limited.
Now if you are talking profiles and desktops I'm afraid I'm just experimenting with those but it appears that once you have your parameters set and you have told the Desktop Manager to use all settings then you can define a number of desktops and profiles. For instance, I most often have 4 17 inch LCD monitors attached to my graphics cards as this gives me plenty of real estate for working in CM2 and doing repairs to assets. So I have a 4 monitor profile and desktop. BUT multiple monitors cause heavy performance loss if in-game so you want a single monitor profile and desktop SLI or non-SLI when in Driver.
I also have a setup for running TS2009 on my 37 inch LCD TV. I have found that an HDMI connection, using in my case a DVI/HDMI adaptor, is far superior than standard TV connection particularly where in-game overlay windows with text are concerned. On standard TV text blooms and is out of focus, whereas it is almost normal on HDMI. Of course a high end computer monitor using dual DVI output and running at 120Hz would be better, but my budget doesn't stretch to that.